(Not Applicable)
(Not Applicable)
The present invention generally relates to a method and an apparatus for detecting metallic objects, and more particularly to an improved method and apparatus for selectively detecting metallic silverware that is intermingled among excess food fragments entering into a receptacle system via a metal detector attached thereto.
The loss of silverware in the food industry has been a consistent and menacing problem throughout the years. With each loss of the silverware, the costs associated with restaurants"" general overhead are inevitably increased. More specifically, restaurants have no other alternatives but to replace the lost silverware since they are vital tools utilized in the business. Depending upon the types of silverware (e.g., forks, spoons, knives, tongs, or the like), the costs for replacing them may be substantial.
The loss of few silverware may not pose to be a serious financial detriment. However, a perpetual loss of the silverware, even few at a time, may become a significant financial concern in which many restaurants cannot ignore. No matter what social classification a particular restaurant belongs to, the loss of silverware may be a burden that all restaurants have in common.
For instance, higher-end restaurants generally use expensive silverware in order to correspond to their upscale image. As such, a loss of even a few may prove to be costly, and such cost may enhance significantly when the loss of silverware becomes perpetual. Even the so-called lower-end restaurants cannot escape the financial burden caused by the loss of their silverware. Although their silverware may not be as expensive as that of the higher-end restaurant""s, the price of replacing them may pose to be a financial concern in view of their general overhead costs. Simply put, many restaurants cannot escape the financial burden caused by the loss of the silverware.
More particularly, the loss of silverware mainly occurs when they are being washed and cleaned. In such situations, food remnants remaining on dirty plates must be disposed of before the plates are washed. Oftentimes, as the silverware are intermingled with the excess food remnants, they may be accidently dropped into a trash receptacle while in the process of dumping the food remnants.
Given the volume of dishes and silverware that typically need to be washed in restaurants, such inadvertent mistakes may go unnoticed. The loss of silverware in the above-described manner may occur frequently, especially during times when restaurants are at their busiest. A need to wash them rapidly in order to meet the flocking customers may further contribute to the problem.
An attempt has been made to address the problem of losing silverware. More specifically, there exists a cover-like device fabricated to be sized and configured to fit over a trash bin. Such device is usually made from plastic material. The cover-like device comprises an angled chute for receiving the excess food fragments therethrough. In other words, restaurant employees would simply dump the excess food fragments from the dirty plates into the angled chute. The cover-like device further includes large powerful permanent magnets that are strategically positioned under the chute. Therefore, large magnets capture any silverware that are accidently dumped into the chute so as to permit only the food fragments to be disposed into the trash bin. Thus, the cover-like device were helpful in partially alleviating the loss of silverware.
However, such prior art device had its limitations. Due to the inherent nature and composition of the magnets, the device only worked with the silverware composed of ferrous metallic materials. As is generally known, ferrous metallic materials are subject to magnetic attraction. In this regard, the magnets of the cover-like device were inoperative when the silverware made of non-ferrous metallic materials was introduced into the angled chute.
Such limitation is a major drawback in preventing the loss of silverware, especially in view of today""s society where the non-ferrous metallic silverware is more abundant than ever. As such, the prior art device puts a significant negative impact upon the purpose that it was originally designed for.
Thus, there has long been a need in the industry, and in the food industry in particular, for a method and an apparatus for mitigating the loss of silverware. In particular, there is a need for an invention that would overcome the deficiency of the prior art device and prevent the inadvertent loss of both ferrous and non-ferrous metallic silverware to the greatest extent possible.
The present invention addresses and overcomes the above-described deficiency of the prior art device by providing a method and apparatus for selectively detecting metallic silverware that is intermingled among excess food fragments entering into a receptacle system via a metal detector attached thereto. More specifically, the metal detector generates a sound tone to alert a user in response to the detection of the silverware within its proximity. In addition, the metal detector is further configured to detect the presence of the metallic silverware composed of either a ferrous metallic material or a non-ferrous metallic material. In this respect, not only does the present invention mitigate the problems of the prior art device, but it also maximizes the purpose that it was designed for.
In accordance with a preferred embodiment of the present invention, there is provided a receptacle system for detecting at least one metallic object entering therein and alerting a user in response to the detection. The system of the preferred embodiment comprises a receptacle body forming an interior cavity. Moreover, a cover may be engaged to the receptacle body, in which the cover may define an opening for providing access to the interior cavity. A metal detector may be attached to the cover to detect the at least one metallic object entering through the opening of the cover. Thereafter, the metal detector may alert the user in response to the detection of the at least one metallic object.
The receptacle body may be fabricated from a plastic or a metallic material, whereas the metal detector and cover may be fabricated from a plastic material. The cover of the preferred embodiment has an inside surface. The inside surface may removably attach the metal detector. The cover may also form a chute. In addition, the cover may be removably engaged to the receptacle body.
In accordance with a preferred embodiment of the present invention, the at least one metallic object may be a type of silverware. The at least one metallic object may be fabricated either from a ferrous or a non-ferrous material. Moreover, the metal detector may further comprise a battery compartment which may be sized and configured to receive at least one battery therein for the purpose of generating power to the metal detector.
In the preferred embodiment, the metal detector may be a pulse induction metal detector capable of generating a series of pulses. Such metal detector may comprise at least one search coil that is receptive of the series of pulses. The at least one search coil may further output a signal in response thereto. The metal detector may further comprise a low pass filter that is receptive of the signal from the at least one search coil to mitigate outside interferences therefrom. In addition, there may be a front-end amplifier circuit for amplifying the signal. The metal detector may further comprise a microcontroller for performing a first sampling and a second sampling upon the signal for the ultimate purpose of generating a sound tone when a programmed threshold is exceeded thereby.
More specifically, the metal detector preferably comprises two search coils so as to be optimal in the environment such as a commercial kitchen, which is filled with horrendously noisy magnetic fields. The output from these coils is connected to the front-end amplifier circuit differentially so that interferences from external, relatively distant magnetic sources would be presented to the front-end amplifier as a common mode signal and thus be rejected. The two search coils are placed side by side so that at least one metallic object falling past them first enters the proximity of one such coil then the other. In this way, since only one coil is encountered at a time, a signal is induced that is not rejected by the differential connection.
In particular, the series of pulses may be communicated to the at least one search coil for approximately 20 microseconds. The search coil may be formed on a printed circuit board, such as a 0.062 inch FR4 circuit board. The series of pulses rapidly terminate to induce a series of eddy currents into the at least one metallic object, if there is/are any, to determine the detection thereof. Moreover, the at least one search coil may be a spiral search coil. The at least one search coil may output the signal after the eddy currents are induced into the at least one metallic object, if any, such that the signal may contain information obtained thereby as to the detection of the at least one metallic object.
Furthermore, the front-end amplifier circuit may be selectively operative only when amplifying the signal to mitigate any unnecessary power consumption. Moreover, the microcontroller may utilize a RC relaxation oscillator and crystal oscillator for regulating precision of high and low speed timing of the metal detector. The microcontroller may further be adapted to alternate between operative and inoperative modes to mitigate any unnecessary power consumption.
In the preferred embodiment, the first sampling and the second sampling may each be performed for approximately 50 microseconds. The metal detector may comprise a differential integrator circuit that is operative to apply complementary inputs to the first sampling and the second sampling. More specifically, the differential integrator compares the first sampling and the second sampling. The microcontroller then uses its analog to digital converter (ADC) to capture the result at the output of the integrator. The microcontroller may be in communication with a speaker for generating the sound tone when the measurements of the first sampling and the second sampling exceed a programmed threshold. A full H-bridge designed circuit may be utilized to drive the speaker. The microcontroller may also be in communication with an RF transmitter for the purpose of triggering a remote sound-generating device. Such communication with the RF transmitter may be needed at times as the speaker built into the metal-detector itself is muffled by the contents of the trash bin, making it hard to hear in the noisy environment of a commercial kitchen, for example.
In accordance with a preferred embodiment of the present invention, the receptacle system further comprises a method of detecting a metallic object entering therein via a metal detector. The preferred embodiment may comprise the method of attaching the metal detector to an inside surface of a cover. Then, disposing the metallic object into an opening of the cover which provides access to an interior cavity of a receptacle body.
The method may further comprise detecting the metallic object with the metal detector as the metallic object progresses to the interior cavity. Next, generating a sound tone to indicate the detection of the metallic object. Finally, retrieving the metallic object from the interior cavity in response to the sound tone.